Solve for $t$ : $-25 = t - 10$
Answer: Add $10$ to both sides: $ \begin{eqnarray} \\ \hphantom{-25 {+ 10}} &\hphantom{=}& \hphantom{t} \\ -25 &=& t - 10 \\ \\ {+10} && {+10} \\ \end{eqnarray} $ $ \begin{eqnarray} \\ -25 {+ 10} &=& t \\ \end{eqnarray} $ Simplify. $ t = -15$